A scion of North Carolina farming families, Thomas Woltz is dismayed when fertile land gives way to suburbs. So Woltz—head of landscape architecture firm Nelson Byrd Woltz (NBW) of San Francisco, New York City, and Charlottesville, Virginia—is turning the tables with projects like the one conceived for Medlock Ames, an organic winery in Sonoma County, California. There, he transformed a defunct gas station into a one-acre paradise with a tasting room and a terrace foaming with native grasses, a feat that earned him the 2013 Honor Award from the American Society of Landscape Architects, where he is a fellow.

Woltz describes the mission of his firm—which employs more than two dozen associates—as “ecologically regenerative” design. Projects range from greening urban gardens to reforesting miles of fragile coastline. Presently on the drawing board is Public Square, a six-acre multipurpose landscape at the center of New York’s Hudson Yards, the much-anticipated mixed-use development that will eventually be the city’s largest. Architectural Digest spoke to Woltz, who lives in Manhattan and Charlottesville, while he was working on a job in New Zealand.

Thomas Woltz:The Smithsonian commissioned NBW to design the National Zoo’s Asia Trail, which leads to its famous panda habitat. The zoologists told Warren Byrd, my mentor and one of our firm’s cofounders, that they needed to keep the animals outdoors during Washington’s muggy summers so visitors could see them. Since pandas prefer cooler temperatures, we conceived rockwork outcroppings with internal coils of chilled water.

AD: NBW works with an astonishing assemblage of consultants, from conservation biologists to cultural historians to Maori tribal leaders. What was one of the most esoteric challenges that called for an extreme specialist to join a project?

TW: Where I am working today, at the century-old Cornwall Park in Auckland, we asked a volcanologist to explain how the early Maori lived around and interacted with the volcano on this 600-acre site. Each expert we hire opens our eyes to different pieces of the puzzle. Our job is to combine those pieces into long-term sustainable use. Here, we are creating a plan for Cornwall Park’s next hundred years.

AD: Much of your work is on a monumental scale. What is one of the very small details that you have enjoyed weaving in?

TW: For a private client we designed a bronze railing cast from branches collected on the jobsite. The railing is a permanent record of several of the native trees in the surrounding forest.

AD: In your firm’s monograph, Garden Park Community Farm (Princeton Architectural Press), there are photographs of one of your projects being set on fire. Why?

TW: Burning grasslands to keep them free of saplings and invasive plants is a traditional practice. At a farm near Charlottesville that we designed and consult on, the meadows are burned every two or three years, allowing nature to rebalance and attract native birds and assuring long-term ecological survival.

AD: The book also features Orongo Station, a 3,000-acre sheep-and-cattle ranch on New Zealand’s North Island. What is happening there?

TW: Overgrazing and other farming practices common in New Zealand threatened miles of the station’s woodlands and wetlands. NBW reforested, replanted, and restored—we even re-established habitats for seabirds migrating from Asia to Antarctica. That’s what I mean by calling our work ecologically regenerative. We take on badly damaged areas, such as quarries and former industrial sites, and rebuild the land to functionality. Life will spring back quickly if you just give it a toehold.

AD: As part of Manhattan’s Hudson Yards project, NBW will be transforming a sprawling industrial site on the city’s far west side into a public square, set among buildings designed by Skidmore, Owings & Merrill; Diller Scofidio + Renfro; and others. Yet you say that it will not be a park. What will it be?

TW: Hudson Yards is not going to be a pastoral space. We see it as an energy-filled plaza, like Piazza San Marco in Venice, but with plants and fountains. All this will be built on a seven-foot-thick concrete slab suspended over working train tracks, right where the High Line, 11th Avenue, and the new No. 7 subway station all come together.

AD: Do you have a garden of your own?

TW: Yes, on a half acre at my home in Charlottesville. I made it myself more than a decade ago and planted each plant, built the walls, and maintained it alone until I got my place in New York two years ago. It’s small, but I have learned so much there. nbwla.com